702-100 Exam Dumps - Linux Professional Institute BSD Specialist

The command locate.updatedb updates the database used by locate to find files. The locate command searches for files by name in a pre-built database of files and directories. The database is usually updated periodically by a cron job, but the locate.updatedb command can be used to manually update it. The command may require root privileges to run, depending on the system configuration. References:

• BSD Specialist Exam 702 Objectives, Topic 715: Basic Unix Skills, 715.4 Searching and Extracting Data from Files
• FreeBSD Handbook, Chapter 7: Finding and Installing Software, 7.2.3 Using locate(1) to Find Files Quickly

The /etc/newsyslog.conf file is the configuration file for the newsyslog command, which is used to rotate log files on BSD systems. The newsyslog command is typically run by cron at regular intervals to check if any log files need to be rotated based on the criteria specified in the /etc/newsyslog.conf file. The file contains a series of entries, one per line, that define the log file name, the owner and group, the mode, the count, the size, the when, the flags, and the pidfile for each log file. For example, the following entry in the /etc/newsyslog.conf file:

/var/log/messages root:wheel 644 7 * @T00 Z /var/run/syslog.pid

means that the /var/log/messages file is owned by root and belongs to the wheel group, has the mode 644, is rotated 7 times, has no size limit, is rotated at midnight every day, is compressed after rotation, and the process ID of syslogd is read from /var/run/syslog.pid and sent a signal to reopen the log file.

The other options are either invalid files or belong to other purposes. For example, /etc/logs.conf is not a valid file, /etc/rc.logd is a startup script for the log daemon, /etc/rc.d/syslogd is a startup script for the syslog daemon, and /etc/syslog.conf is the configuration file for the syslog daemon.

References:

• [newsyslog.conf] - FreeBSD newsyslog.conf(5) Manual Page
• [newsyslog] - FreeBSD newsyslog(8) Manual Page
• [Log File Rotation] - FreeBSD Handbook

The command cp SI 52 in the Bourne shell script copies the file named by the value of SI to the file named 52. The SI is a positional parameter that represents the first argument passed to the script when it is executed. Positional parameters are numbered from 1 to 9, and can be accessed by using the dollar sign $ followed by the number. For example, $1 is the first positional parameter, $2 is the second, and so on. Therefore, the SI in the script is equivalent to $1, and it represents the first argument passed to the script. The correct answer is D. A positional parameter. References:

• [Positional Parameters - FreeBSD]
• [Shell Scripting Tutorial - Positional Parameters]

The date command in BSD systems provides the following features:

• It outputs the time in a specific format. The date command can display the current date and time in various formats, depending on the options and arguments given. For example, the command date +%Y-%m-%d will output the date in the format of year-month-day, such as 2023-04-30. The command date +%T will output the time in the format of hour:minute:second, such as 22:51:42. The command date +%A will output the full name of the weekday, such as Thursday. The date command supports many formatting characters that can be used to customize the output. For a full list of formatting characters, see the date(1) manual page1.
• It sets the clock to a specific time. The date command can also be used to set the system date and time, if the user has the appropriate privileges. For example, the command date 0430225123 will set the date and time to April 30, 2023, 22:51:42. The command date -u 0430225123 will set the date and time to the same value, but in UTC (Coordinated Universal Time) instead of the local time zone. The command date -n will set the date and time to the current network time, using the ntpd(8) daemon1.

The date command does not provide the following features:

• It does not display a calendar. The date command only displays the date and time, not a calendar. To display a calendar, the cal(1) or ncal(1) commands can be used instead. For example, the command cal 4 2023 will display the calendar for April 2023. The command ncal -w 2023 will display the calendar for the whole year 2023, with week numbers23.
• It does not send NTP queries. The date command does not send any network requests or queries to NTP (Network Time Protocol) servers. To synchronize the system clock with NTP servers, the ntpd(8) daemon or the ntpdate(8) utility can be used instead. For example, the command ntpd -q will query one or more NTP servers and adjust the system clock accordingly. The command ntpdate pool.ntp.org will set the date and time to the value returned by the NTP server pool.ntp.org45.
• It does not change the system’s timezone. The date command does not change the system’s timezone setting, only the date and time values. To change the system’s timezone, the tzsetup(8) utility or the ln(1) command can be used instead. For example, the command tzsetup will run an interactive program that allows the user to select a timezone from a list of regions and cities. Thecommand ln -sf /usr/share/zoneinfo/Europe/Paris /etc/localtime will create a symbolic link from the file /etc/localtime to the file /usr/share/zoneinfo/Europe/Paris, which contains the timezone information for Paris, France . References:
• date(1) - FreeBSD
• cal(1) - FreeBSD
• ncal(1) - FreeBSD
• ntpd(8) - FreeBSD
• ntpdate(8) - FreeBSD
• [tzsetup(8) - FreeBSD]
• [ln(1) - FreeBSD]

The pw utility is a command-line utility for the FreeBSD system user and group files, allowing the superuser an easy way of adding, modifying and removing users and groups. To lock a user account on a FreeBSD system, the pw lock command can be used with the username as an argument. This will prevent the user from logging in orchanging their password. To unlock a user account, the pw unlock command can be used with the username as an argument. This will restore the user’s access to the system. References:

• FreeBSD locking an account - nixCraft
• FreeBSD: How To Add, Delete Or Modify Users
• How to: FreeBSD User Administration - Atlantic.Net

The question mark (?) is a special character in regular expressions that modifies the preceding expression to match zero or one times. For example, the regular expression colou?r matches both color and colour, but not colouur or colr. The question mark is also used to make an expression non-greedy, meaning that it will match the shortest possible string instead of the longest. For example, the regular expression <.?> matches the first pair of angle brackets in a string, while <.> matches the entire string enclosed by the outermost pair of angle brackets. References:

• Regular expression - Wikipedia, section “Basic concepts”
• How to write Regular Expressions? - GeeksforGeeks, section “Special Characters”

Compiling an application from source code allows for customization of the binary to a system’s particular needs, including optimization for specific hardware and enabling or disabling certain features. Pre-compiled binaries are quick and easy to install but they don’t allow for such customization.

References:

• Understand the difference between a pre-compiled binary and compiling from source

The file command is used to determine the type of data contained in a computer file. It performs a series of tests on the file and prints a description of the file type based on the first successful test. The file command can take one or more file names as its arguments. For example, file mybackup will display the file type of mybackup. The other options are not valid commands for finding the file type. References:

• file command in Linux with examples
• file (command) - Wikipedia
• Linux File Command

A symbolic link, or symlink, is a special type of file that points to another file or directory on the file system1. When creating a symbolic link with the ln command, the syntax is as follows:

ln -s target link

where target is the file or directory to link to, and link is the name of the symbolic link2. If the link name already exists, the ln command will fail and display an error message indicating that the target already exists3. This is because the ln command does not overwrite existing files or directories by default4. Therefore, the only way to create a symbolic link with the same name as an existing file or directory is to manually remove the existing target first, and then run the ln command again. Alternatively, the ln command can be used with the -f (force) option, which will remove the existing target and create the symbolic link in one step4. However, this option is not mentioned in the question, so the correct answer is A.

References: 1: How to Create Symbolic Links in Linux [Complete Guide] - Linux Handbook 2: Ln Command in Linux (Create Symbolic Links) | Linuxize 3: How to Create and Use Symbolic Links (aka Symlinks) on Linux - How-To Geek 4: Symbolic Links in Unix/Linux - Stack Abuse

Nmap is a program that can be used to enumerate all responsive hosts on a subnet. Nmap stands for Network Mapper, and it is a tool that can perform network discovery, port scanning, service detection, vulnerability assessment, and more. Nmap can send different types of packets to probe the hosts on a subnet and determine which ones are alive and what services they are running. Nmap can also perform OS fingerprinting, which can identify the operating system of the target hosts. Nmap has many options and features that can customize the scan according to the user’s needs and preferences. The other programs are not suitable for enumerating all responsive hosts on a subnet, because:

• A. traceroute: This program is used to trace the route of packets from the source host to the destination host. It can show the intermediate hops and the latency of each hop. However, it cannot show all the hosts on a subnet, only the ones that are on the path to the destination.
• B. netstat: This program is used to display the status of network connections, routing tables, interface statistics, and more. It can show the local and remote addresses and ports of the active connections, but it cannot show all the hosts on a subnet, only the ones that are connected to the local host.
• D. rtso1: This is not a valid program name, but it may be a typo for rtso, which is a program that can perform TCP SYN scanning. However, this program is not as versatile and powerful as nmap, and it can only scan TCP ports, not UDP or other protocols.
• E. route: This program is used to manipulate the routing table, which is used to determine the next hop for a packet based on its destination address. It can show the destination, gateway, interface, and flags of each route, but it cannot show all the hosts on a subnet, only the ones that are reachable via a specific gateway. References: 6: https://nmap.org/book/man.html 7: https://www.freebsd.org/cgi/man.cgi?query=traceroute&sektion=8 : https://www.freebsd.org/cgi/man.cgi?query=netstat&sektion=1 : https://www.freebsd.org/cgi/man.cgi?query=rtso&sektion=1 : https://www.freebsd.org/cgi/man.cgi?query=route&sektion=8

The zfs snapshot command creates a snapshot of a ZFS dataset, which is a point-in-time copy of the data. The snapshot name is specified as follows: filesystem@snapname or volume@snapname. The snapshot name must satisfy the naming requirements in ZFS Component Naming Requirements1. In this case, the command zfs snapshot space/data@snap1 creates a snapshot of the dataset space/data named snap1. The other options are either invalid or do not create a snapshot. References: 1:https://docs.oracle.com/cd/E19253-01/819-5461/gbcya/index.html

In FreeBSD, theunamecommand is used to display system information. The option-vspecifically displays the version of the running operating system. This information is critical for system administrators and users who need to know the exact version of the OS they are working with, particularly when troubleshooting, updating, or configuring the system for specific software requirements.

https://man.freebsd.org/cgi/man.cgi?query=uname &sektion=1&format=html

The -v or --version option of the uname command displays the version level of the operating system. This is a string that identifies the release date and patch level of the system. For example, on FreeBSD, the output would be something like:

FreeBSD 13.0-RELEASE-p4 #0: Tue Aug 24 07:12:34 UTC 2021

This indicates that the system is running FreeBSD 13.0, with the fourth patch applied, and that the kernel was built on August 24, 2021. The version level can be useful to determine the compatibility and security of the system, as well as to report bugs or issues.

The adduser.conf file is used to store the default settings for the interactive adduser script on BSD systems. The adduser script is a shell script that uses the pw command to add new users to the system. It creates passwd/group entries, a home directory, copies dotfiles and sends the new user a welcome message. The adduser.conf file allows the administrator to pre-set certain configuration options, such as the default shell, home partition, login group, encryption method, etc. The other options are either invalid files or belong to other purposes. For example, login.conf is used to define login classes, pw.conf is used to configure the pw command, user.conf is used to set user-specific kernel variables, and usermgmt.conf is used to configure user management utilities. References:

• adduser - FreeBSD adduser(8) Manual Page1
• adduser.conf - FreeBSD adduser.conf(5) Manual Page2
• [pw] - FreeBSD pw(8) Manual Page

The file /etc/rc.conf contains values for Management Information Bases (MIBs) which are set during system startup. This file is used to configure system-wide settings, including the enabling and disabling of services, network settings, and other startup configurations2.

References:

• FreeBSD Handbook - The FreeBSD Booting Process

The file /etc/hostname.em0 contains the configuration for the network interface em0 on an OpenBSD system. This file specifies the IP address, netmask, gateway, and other options for the interface. The file is read by the netstart script during boot or when the interface is restarted. The file name is derived from the interface name, which is usually based on the driver name and the device number. For example, em0 is the first interface using the em driver, which supports Intel PRO/1000 network adapters.

References:

• Networking | OpenBSD Handbook
• [hostname.if(5) - OpenBSD manual pages]